The present invention relates to a tape measure wherein a flexible measuring tape is accommodated in a case.
A tape measure including a flexible measuring tape accommodated inside a case is wound about a winding drum inside the case. A tension spring is attached to the winding drum, and when the measuring tape is pulled out, this spring is tensioned and stores a spring force. When the user releases his or her hand from the pulled out measuring tape, it automatically winds up into the case, due to the force of the spring.
However, in the winding up operation, as an accelerating force is applied, the speed of winding of the measuring tape gradually increases, and in addition to this, the increase in the winding speed is also promoted by the growth of the winding diameter as the tape is wound in, thereby leading to problems in that the measuring tape becomes twisted, or strikes the fingers of the person holding the case, or the like.
As a countermeasure to this, tape measures incorporating a braking mechanism are used in order to suppress the winding speed.
Moreover, a problem also arises in that, when measuring with the measuring tape in an extracted state, the measuring tape may be retracted into the case unintentionally. Therefore, tape measures are also used which incorporate a locking mechanism in addition to the aforementioned braking mechanism, the tape measure being lockable by operating this mechanism, in such a manner that the extracted tape cannot be retracted from a desired position.
In the tape measure described in Japanese Patent Application Laid-Open Publication No. 10-89901, a brake button is provided on the side face of a case, and by pressing on this brake button with a finger, the brake button engages with a side face of a winding drum, thereby halting or braking the rotation of the winding drum.
A brake button is also provided on the upper portion of the front face of the case, and by pressing this brake button with a finger, the brake button engages with a side face of the winding drum (collar of the winding drum), and hence it can also be used for the function of halting or braking the rotation of the winding drum.
In the tape measure described in Japanese Utility Model Application After-Examination Publication No. 49-39338, by extending one side of the rotating axle of a winding drum to the outer side of a case, by means of a circular hole provided in a side face of the case, a mechanism for halting or braking the rotation of the winding drum is provided, by directly touching a finger against the winding drum.
These braking mechanisms apply a braking action by frictional contact of a member or a finger against the winding drum, but they do not provide a locking mechanism. Although it is possible to halt the measuring tape when extended, by continuous operation of the braking mechanism, since the measuring tape winds in when the user releases his or her hand, this is problematic in that it makes measurement difficult to perform.
In the tape measure described in Japanese Utility Model Application After-Examination Publication No. 41-10935, an elastic braking member is provided slidably on the inner side of the front wall of a case, and by a downward operation of this braking member, the measuring tape is wedged against the case wall and held in its extended state.
In the tape measures described above, it is possible to apply a brake whilst retracting the extended tape, by reducing the pressing amount of the elastic braking member, but this entails a problem in that the measuring scale may become worn by means of the end portion of the elastic braking member rubbing against the measuring tape moving at high speed.
In the tape measure disclosed in Japanese Utility Model Application Laid-Open No. 59-47802, in addition to a locking mechanism similar to that in the tape measure described in Japanese Utility Model Application After-Examination Publication No. 41-10935, a curved braking elastic piece is provided, which provides braking by making contact with a drum, but since the locking mechanism and braking mechanism are constituted by separate parts, there is a problem in that the number of components increases.
The present invention was devised with the foregoing in view, an object thereof being to provide a tape measure having simple operation, wherein a brake can be applied to a winding drum, and furthermore, an extracted measuring tape can be locked in position, by means of a single component.
According to the present invention, there is provided a tape measure having an operating member installed to be movable on the side of a main case, and including a braking piece in the rear portion thereof and a locking piece in the front portion thereof, wherein a braking action is provided by means of the braking piece making contact with the periphery of a winding drum when the operating member is pressed radially inward when in a rearward circumferential position of the operating member, and a measuring tape is locked by means of the locking piece being pressed against the measuring tape when the operating member is moved to a forward circumferential position thereof.
Preferably, the operating member includes a lock position holding projection, and the operating member is held in a lock position by means of the lock position holding projection engaging with the main case, when the operating member is moved to the forward position.
Preferably, an engaging member which is engageable with an engaging member provided on the main case is provided in the rear portion of the operating member.
Preferably, the operating member has a curved shape which follows the outer circumference of the winding drum.
Preferably, the operating member is made from a flexible material.
Preferably, the operating member is made from a synthetic resin, such as polyacetal, or the like.
Preferably, the main case includes a receiving section in order that the measuring tape can be held between the locking piece and the receiving section.
Preferably, a guide section for guiding the movement of the operating member is provided in the main case, and the side faces of the operating member are slidably in contact with the guide section.
Preferably, a pair of the guide sections are provided on the inner side and outer side in the radial direction, a groove being formed in the position between these guide sections, and a flange section provided on the operating member being accommodated in the groove.
Preferably, a lock position holding projection is provided on the flange section, and the lock position holding projection engages with the end portion of the guide section provided on the inner side in the radial direction, whereby the measuring tape is held in a lock position.
The present invention also provides a tape measure that includes a winding drum having a tension spring for automatically winding in a drawn out measuring tape, accommodated inside a main case, and an operating member for imparting a braking or locking action by making contact with the winding drum or the measuring tape. The operating member is installed to be movable circumferentially in a forward and backward direction on the main case. The operating member is formed in a curved shape from a flexible material, a braking piece being provided in the rear portion of the operating member, a locking piece being provided in the front portion thereof, and a knob projecting from the main case being provided in the middle portion thereof when the operating member is in a rearward position, and released it assumes a state of non-contact with either the winding drum or the measuring tape, thereby allowing the measuring tape to be drawn out or wound in freely, when the operating member is pressed radially inward the rear portion is deflected and the braking piece makes contact with the periphery of the winding drum, thereby applying a brake to the measuring tape. When the knob is pressed from the aforementioned state towards the inside of the main case. When operating member is moved circumferentially to an intermediate forward position, the locking piece makes contact with the measuring tape, thereby applying a brake to the measuring tape. When the knob is pressed forwards to an intermediate position. When operating member is moved to a forward circumferential position the front portion becomes deflected, and the measuring tape is held between the locking piece and the main case, thereby locking the measuring tape.
Preferably, the operating member includes a lock position holding projection, and the lock position holding projection engages with the main case, thereby holding the operating member in a lock position, when the operating member is moved to the forward position.
Preferably, an engaging section which is engageable with an engaging section provided on the main case is provided in the rear portion of the operating member, the engaging section of the operating member being engaged, thereby restricting the forward and backward movement of the operating member, in a normal state where the knob is released, and the engagement being released when pressure is applied to the knob.
Preferably, the operating member has a curved shape following the outer circumference of the winding drum.
Preferably, the main case includes a receiving section in order that the measuring tape can be held between the locking piece and the receiving section.
Preferably, a guide section for guiding the movement of the operating member is provided in the main case, and the side faces of the operating member are slidably in contact with the guide section.
Preferably, a pair of the guide sections are provided on the inner side and outer side in the radial direction, a groove being formed in the position between these guide sections, and a flange section provided on the operating member being accommodated in this groove.
Preferably, a lock position holding projection is provided on the flange section, and the lock position holding projection engages with the end portion of the guide section provided on the inner side in the radial direction, thereby locking the measuring tape in position.